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1.
J Fungi (Basel) ; 9(3)2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36983505

ABSTRACT

Late leaf rust is a fungal disease in raspberries caused by Aculeastrum americanum (Farl.) M. Scholler U. Braun (syn. Thekopsora americana (Farl.) Aime McTaggart) leading to early defoliation and yield losses. Red raspberries (Rubus idaeus L.) are susceptible to this pathogen, although this susceptibility varies among cultivars. In contrast, black raspberries were previously reported to be more resistant (Rubus occidentalis L.) and immune (Rubus niveus Thunb.) to this pathogen, raising their importance in plant breeding programs. However, what features make them respond differently to the same pathogen? In this study, we characterize for the first time the pre- and post-formed structural and biochemical defense mechanisms of R. idaeus cv. Autumn Bliss, R. occidentalis and R. niveus. Ultrastructural and histopathological analyses were used to uncover the interactions between these raspberries and A. americanum. The ultrastructural results indicate that the pathogen germinates on both leaf surfaces but can only form appressoria on the stomata. Although the three raspberry species were infected and colonized by A. americanum, a clear difference in susceptibility was observed between them. A compact mesophyll, pre- and post-formed phenolic compounds, and post-formed pectic compounds were the main plant defense mechanisms against fungal colonization. These findings provide new information about raspberries' defense mechanisms in response to A. americanum and elucidate the interactions occurring in these pathosystems.

2.
J Ornithol ; 159(1): 129-140, 2018.
Article in English | MEDLINE | ID: mdl-31998596

ABSTRACT

In recent decades, arboreal Darwin's Finches have suffered from a dramatic population decline, which has been attributed to parasitism by the invasive botfly Philornis downsi. However, changes to their primary habitat caused by invasive plant species may have additionally contributed to the observed population decline. The humid cloud forest on Santa Cruz Island is a stronghold of arboreal Darwin's Finches but has been invaded by blackberry (Rubus niveus). In some areas, manual control and herbicide application are used to combat this invasion, both causing a temporary removal of the entire understory. We hypothesized that the removal of the understory reduces the availability of arthropods, which are a main food source during chick rearing. We compared the foraging behaviour of Warbler Finches (Certhidea olivacea) and Small Tree Finches (Camarhynchus parvulus) at three study sites that varied in the degree of R. niveus invasion and the length of time since the last herbicide application. We used prey attack rate and foraging success as an index for food availability and predicted a lower attack rate and foraging success in areas that had recently been sprayed with herbicides. We found that both the invasion and the management of R. niveus influenced microhabitat use, foraging substrate and prey choice in both species. Contrary to our hypothesis, we did not find a lower attack rate or foraging success in the area with recent herbicide application. This may be explained by the finding that both species mainly foraged in the canopy but also used dead plant structures of the understory of the recently controlled area that resulted from the invasive plant management.

3.
Ciênc. rural (Online) ; 48(3): e20161023, 2018. tab
Article in English | LILACS | ID: biblio-1045090

ABSTRACT

ABSTRACT: The framboseira-negra has a potential for cultivation in Brazil, due to the fact that this fruit produces high quantities of fruits, which confer a high quality jelly. However, their propagation is an obstacle to the establishment of commercial plantations. Production and expansion of a fruit is directly linked to the propagation method and the quality of its development. Given the above, the aim of the present study was to evaluate the use of stem cuttings and IBA in asexual propagation of black raspberry. Two experiments being conducted in greenhouse conditions were performed. Stem cuttings were taken from didactic orchard, with matrix plant of four years, which were the experiments. The first experiment was carried out in factorial 3x2, with cuttings taken from three regions of the plant branch matrix (apical, median and basal) x two treatments with IBA (without IBA and 2000mg L-1 IBA), containing four repetitions and fifteen cuttings per repetition. The second experiment consisted of a 4x2, with four sizes of cuttings (5, 10, 15 and 20cm) x two treatments with IBA (without IBA and 2000mg L-1 IBA), with four replications and fifteen cuttings by repetition. After eighty days, the percentage of rooted cuttings (%), average number of roots and shoots for cuttings, the longest root length (cm) and fresh and dry biomass of shoots (g) were assessed. Best results in the formation of root system were observed in middle and apical stem cuttings. Stem Cuttings between 10 and 20cm obtained better results for rooting. There is no need to use IBA rooting of cuttings of black raspberry.


RESUMO: A framboseira-negra possui potencial de cultivo no Brasil pelo fato dessa fruteira produzir altas quantidades de frutos que conferem uma geleia de alta qualidade. No entanto, a sua propagação é um entrave no estabelecimento de plantios comerciais. Diante do exposto, objetivou-se, com o presente trabalho, avaliar a utilização da estaquia caulinar e ácido indolbutírico na propagação assexuada de framboeseira-negra. Foram realizados dois experimentos, sendo conduzidos em condições de telado. Estacas caulinares foram retiradas de pomar didático de plantas matrizes de quatro anos, as quais constituíram os experimentos. O primeiro experimento foi elaborado em esquema fatorial 3x2, sendo as estacas retiradas de três regiões do ramo da planta matriz (apical, mediana e basal) x dois tratamentos com ácido indolbutírico (sem AIB e 2000mg L-1 de AIB), contendo quatro repetições e quinze estacas por repetição. O segundo experimento constituiu-se de esquema fatorial 4x2, sendo quatro tamanhos de estacas (5, 10, 15 e 20cm) x dois tratamentos com ácido indolbutírico (sem AIB e 2000mg L-1 de AIB), contendo quatro repetições e quinze estacas por repetição. Após oitenta dias, avaliaram-se a percentagem de estacas enraizadas (%); número médio de raízes e de brotações por estacas; comprimento da maior raiz (cm) e biomassa fresca e seca das brotações (g). Melhores resultados na formação do sistema radicular foram observados em estacas caulinares medianas e apicais. Estacas caulinares entre 10 e 20cm obtiveram melhores resultados para enraizamento. Não há necessidade de utilização de AIB no enraizamento de estacas caulinares de framboeseira-negra.

4.
J Ethnopharmacol ; 164: 89-95, 2015 Apr 22.
Article in English | MEDLINE | ID: mdl-25681544

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Rubus niveus Thunb. plant belongs to Rosaceae family and have been used traditionally to treat wounds, burns, inflammation, dysentery, diarrhea and for curing excessive bleeding during menstrual cycle. The present study was undertaken to investigate the in vivo genotoxicity of Rubus niveus aerial parts extract and its possible chemoprotection on doxorubicin (DXR)-induced DNA damage. In parallel, the main phytochemicals constituents in the extract were determined. MATERIALS AND METHODS: The animals were exposed to the extract for 24 and 48 h, and the doses selected were 500, 1000 and 2000 mg/kg b.w. administered by gavage alone or prior to DXR (30 mg/kg b.w.) administered by intraperitoneal injection. The endpoints analyzed were DNA damage in bone marrow and peripheral blood cells assessed by the alkaline alkaline (pH>13) comet assay and bone marrow micronucleus test. RESULTS AND CONCLUSION: The results of chemical analysis of the extract showed the presence of tormentic acid, stigmasterol, quercitinglucoronide (miquelianin) and niga-ichigoside F1 as main compounds. Both cytogenetic endpoints analyzed showed that there were no statistically significant differences (p>0.05) between the negative control and the treated groups with the two higher doses of Rubus niveus extract alone, demonstrating absence of genotoxic and mutagenic effects. Aneugenic/clastogenic effect was observed only at 2000 mg/kg dose. On the other hand, in the both assays and all tested doses were observed a significant reduction of DNA damage and chromosomal aberrations in all groups co-treated with DXR and extract compared to those which received only DXR. These results indicate that Rubus niveus aerial parts extract did not revealed any genotoxic effect, but presented some aneugenic/clastogenic effect at higher dose; and suggest that it could be a potential adjuvant against development of second malignant neoplasms caused by the cancer chemotherapic DXR.


Subject(s)
Chromosome Aberrations/drug effects , DNA Damage/drug effects , Plant Extracts/pharmacology , Rubus , Animals , Antibiotics, Antineoplastic/adverse effects , Chromosome Aberrations/chemically induced , Comet Assay , Doxorubicin/adverse effects , Glucosides/analysis , Male , Mice , Micronucleus Tests , Mutagens/adverse effects , Neoplasms/prevention & control , Plant Extracts/chemistry , Quercetin/analogs & derivatives , Quercetin/analysis , Saponins/analysis , Stigmasterol/analysis , Triterpenes/analysis
5.
Ciênc. rural ; 42(3): 418-422, mar. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-623049

ABSTRACT

Visando estudar técnicas de propagação vegetativa da framboeseira negra (Rubus niveus) por estaquia e mergulhia, o objetivo do presente trabalho foi verificar o potencial rizogênico de estacas caulinares, radiculares, mergulhia de ponta e alporquia dessa espécie. No primeiro experimento, estacas radiculares e caulinares de 10 cm foram tratadas com diferentes concentrações de ácido indolbutírico (AIB): 1000, 2000, 3000 e 4000mg L-1 por 10 segundos, além do controle composto somente por água. No segundo experimento, as estacas foram armazenadas a frio por 10, 20 e 30 dias, além do controle sem armazenamento. Em ambos os experimentos, as estacas caulinares foram enterradas 2/3 de seu comprimento na posição vertical e as estacas radiculares foram totalmente imersas na posição horizontal, utilizando a vermiculita de grânulos finos como substrato, em telado com sombreamento de 50% e, após 60 dias, foram avaliadas. No terceiro experimento, a mergulhia de ponta e alporquia foram realizadas na porção mediana dos ramos, aplicando-se no local diferentes concentrações de AIB (0, 1000, 2000 e 3000mg L-1) e, em seguida, foram envolvidos pelo substrato casca de pinus umedecido. Passados 45 dias, foram removidos para a mensuração. Concluiu-se que as estacas caulinares apresentam resultados superiores em comparação com as estacas radiculares, não necessitando armazenar a frio e não tratar com AIB; a mergulhia de ponta promoveu maior emissão de raízes em comparação com a alporquia.


Aiming to develop a propagation protocol through black raspberry (Rubus niveus) cutting and layering, the objective of the present research was to quantify the rizogenic potential of stems and roots cuttings, point and air layering of this specie. In the first experiment, the stems and roots cuttings of 10 cm of length were treated with different concentrations of indolbutyric acid (IBA): 1000, 2000, 3000 and 4000mg L-1 for 10 seconds. In the second experiment, the stems and roots cuttings of black raspberry were cold storage by 10, 20 and 30 days, and control without storage. In both experiments, the stems cuttings were buried 2/3 length in the vertical position and the roots cuttings were totally immerged in the horizontal position, using the vermiculita as substrate, in greenhouse with 50% of light. After 60 days, they were evaluated. In the third experiment, the point and air layering were accomplished in the medium portion of the branches, being applied in the place different concentrations of IBA (0, 1000, 2000 and 3000mg L-1) and soon after, they were involved by the following humidified pinus substrate. After 45 days they were removed for the evaluation. It can be concluded that the stems cuttings presents better results in comparison by roots cuttings, owing cold storage and without IBA; the point layering promoted larger emission of roots in comparison to air layering.

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